function [U, V] = dftuv(M, N)
% DFTUV Computes meshgrid frequency matrices.
%   [U, V] = DFTUV(M, N) computes meshgrid frequency matrices U and
%   V.  U and V are useful for computing frequency-domain filter
%   functions that can be used with DFTFILT.  U and V are both  M-by-N.
   
% Set up range of variables.
u = 0:(M - 1);
v = 0:(N - 1);
    
% Compute the indices for use in meshgrid.
idx = find(u > M/2);
u(idx) = u(idx) - M;
idy = find(v > N/2);
v(idy) = v(idy) - N;
    
% Compute the meshgrid arrays.
[V, U] = meshgrid(v, u);

end  % ending function

    